On: The cpu_features library

[jcranmer]

CPUID on x86 is a user-level instruction. When you're doing processor-assisted emulation, CPUID is an instruction that does cause an exit to the hypervisor, which does allow you to do CPUID emulation. You clearly don't need such instructions to be privileged to do emulation games with CPUID.

[valarauca1 → jcranmer]

>You clearly don't need such instructions to be privileged to do emulation games with CPUID.

There are configuration registers which can make CPUID a privileged instruction.